Means for and method of feeding cleaning materials to feed water heaters



ov. 5, 1935. ,R M. QSTERMANN v 2,019,628 I MEANS FOR AND METHOD OF FEEDING CLEANING MATERIALS To FEED WATER HEATERS Flled July 29, 1933 2 Sheets$heet l A Aw \Q 4 WM.

v ATTORNEY Nov. 5, 1935. v R. M. OSTERMANN MEANS FOR AND METHOD OF FEEDING CLEANING MATERIALS TO FEED WATER HEATERS Filed July 29, 1953 2 Sheets-Sheet 2 BY W ATTORNEY Patented Nov. 5, 1935 PATENT OFFICE MEANS FOR AND METHOD OF FEEDING CLEANING MATERIALS TO FEED WATER HEATERS Rudolf M. Ostermann, Kenilworth, Ill., assignor to The Superheater Company, New York, N. Y.

Application July 29, 1933, Serial No. 682,821

8 Claims. (01. 122-379) My invention relates to the art of steam heated feed water heaters.

Tannin and other treating materials or cleaning substances have been employed for removing the scale formed on the inner surfaces of the coils of closed type feed water heaters of locomotives, such treating materials having commonly been applied in the round house.

It is an object of my invention to provide a method and apparatus adapted to apply scale removing or treating materials to the inner surfaces of the tubes of closed type feed water heaters of locomotives between runs of the feed pump when on the road and for then heating such surfaces to insure a rapid and complete reaction between the treating material and such scale as may have been deposited on the interior of the coil or coils so as to maintain an optimum average rate of heat transfer to the feed-water.

In order that my invention, together with its objects and advantages, may be fully and readily understood, I will now describe in detail in connection with the accompanying drawings an arrangement selected by way of example from a number of possible embodiments of the invention, and one adapted to operate in accordance with my novel method. In the drawings,

Fig. 1 is an elevational view of a portion of a locomotive boiler and smoke box provided with a closed type feed water heater and an arrangement for applying treating material to such heater in accordance with my invention.

Fig. 2 is a sectional view of a chamber for condensing steam and dissolving treating material shown in Fig. 1.

Fig. 3 is a horizontal sectional view through chamber of Fig. 2.

Fig. 4 is a sectional detail view of an automatic drain valve shown in Fig. 1.

Fig. 5 is a sectional view of a slow acting stop Valve shown in Fig. l.

The arrangement illustrated in the drawings include a forward portion III of a locomotive boiler, supported from the smoke box I2 of which is a feed water heater I 4 of the closed type in which feed water for boiler I is heated by exhaust steam while passing through pipes I within the heater. Heater I I is shown as having an inlet It and outlet I8 for feed water for boiler I0, the exhaust steam connections for heater I4 not being shown. A pump 20 is connected to receive water from the tender, not shown, and to force the same through pipe connections 22 containing a check valve 24 to the inlet I6. After passing through the coils or pipes I5 within the heater I4, the water from pump 20 comes out at point I8 and is conducted to the boiler I0 through line 26 containing a check valve 28.

Now my experience has shown that a thin film 5 of scale may form on the inner surface of heating tubes of closed type heater very quickly, that is to say during any single run of the pump 20. Such a film of scale, in spite of its extreme thinness, has a noticeable effect in reducing the transfer of heat from the exhaust steam to the feed Water as compared to the heat transfer when the surfaces of the pipes or coils are entirely clean. In accordance with my invention, therefore, I apply cleaning substance to the inner or water touched surface of the heater between each two successive periods of operation of feed water pump 29 and have devised means for accomplishing such step automatically. However, it is undesirable to employ a cleaning agent such as 2 a mineral acid which, even though dilute, might attack the metal of the tubes at spots not covered by the film of scale, and I prefer to use an agent or compound which requires that the temperature of the cleaning agent and scale be raised materially to ensure a complete reaction after such agent has been applied. I prefer, as a matter of fact, to use tannin and to bring the temperature of the tannin up substantially to that of the steam in the boiler I0 almost immediately after 30 it has been applied to the tube surfaces and always do so before the next run or period of operation of the pump 20 irrespective of the cleaning agent used. Means for this purpose also are provided as will presently appear. Such method of operation not only keeps the scale film at a minimum average thickness, but utilizes the treating or-scale removing material with maximum economy.

In the arrangement shown, a chamber 30 is provided adapted to contain a block 32 of tannin or like cleaning material and the upper part of chamber 30 is connected by means of pipe 34 to the steam space of the boiler at 36. The lower portion of chamber 30 is connected by internal channels 38 (Fig. 2) and pipe 40 with the outlet I8 of the heater I4 at the point 42. Pipe 34 contains a cut-off whose handle is shown at 44 and pipe 49 contains a check valve 43 arranged to permit flow from chamber 30 into connection I8 50 but preventing back flow of water from point 42 to the chamber 30. Connected to the inlet I6 of the heater I 4: at the point 45 is a drain pipe 46. Pipe 46 is to be closed except for a relatively short period immediately after the termination of each run of pump 20, at which times pipe 46 is open for a period to permit treating or cleaning materials from chamber 3!] to flow through and coat the coils in the heater 14. Hand operated means may be employed for this purpose, but I prefer to employ automatic means instead. As shown, pipe 46 contains the casing of an automatic valve 48 (Fig. 4) whose valve member 50 is automatically held off its seat when the pump is stopped by a piston 52a pressed down by spring 52. Valve 50 is automatically seated by the spring 53 when the pump is in operation to prevent waste of water at such times through pipe 46. To permit such action, the arrangement is such that pump pressure enters casing 48 beneath piston 52a and that such piston overpowers spring 52 when the pump is running to permit spring 53 to close the valve 50 against the pump pressure.

In the pipe 45 also preferably is the casing 54 (Fig. 5) of a slow closing automatic valve whose valve member 56 is connected by spindle 58 to a piston 60 adapted to hold the valve member 56 off its seat in opposition to the spring 62 which tends to close member 56. The pressure of spring 62 also tends to hold valve 56 in closed position. Spindle 58 extends through casing 54 at the side opposite the cylinder 6| of piston 60 and is provided at the end opposite such piston with a second piston 64 against which the spring 62 presses. Spring 62 automatically initiates a closing action of valve member 56 as soon as pressure in pipe 22 and cylinder 6| has been relieved. Waste of boiler steam is thus prevented. The outer face of piston 54 is in contact with the air in a dash-pot chamber 66. Such dash-pot chamber acts with piston 64 in the usual manner of dash-pots to determine the time required by spring 62 to close valve 56 whenever there is no pressure against the piston 60 to hold such valve open. When pump 20 is in operation, fluid is supplied to the cylinder 6| on the valve side of piston 60 by a pipe 68 so as to hold the valve 56 open. As shown, pipe 68 connects at one end with pipe 22 so that a pressure at least as great as that in boiler I0 is available in cylinder 6| when the pump 20 is running. The pump 20 being of the centrifugal type and pipe 68 being connected to pipe 22 between pump 20 and check valve 24, the pressure on piston 69 drops very rapidly, as soon as the pump 28 is shut down, from boiler pressure or above almost to atmospheric, because the pressure is relieved through pipes 68 and 22 and pump 20 until the pressure on piston 6!! becomes substantially equal to that in the suction line of pump 20. However, I do not limit myself to any particular source of pressure for operating piston 6E! so long as the pressure of the source used goes up when the pump 20 is running and down when it is not. In fact, I do not limit myself to operating valve member 56 by pressure, but may operate it by hand or use any means adapted to provide a delayed closing action of member 56.

Moreover, the dashpot 65 is designed and adjusted to prevent the closing of valve 56 for a period of time after each stoppage of pump 20 to permit steam to follow the cleaning material down into the coils [5 to raise the cleaning material and scale to reacting temperature.

The steps of my method and the operation of my apparatus will be evident from the foregoing description of the apparatus. However, my novel method or process and the operation of my apparatus may, for purposes of convenience be stated as follows:

The pump 20 forces feed water through the heater [4 and into boiler ll], such water being pre-heated in coils l5 within the heater by heat from exhaust steam. Each period of operation of pump 20 is usually long enough so that a certain amount of scale is formed on the inside surfaces of coils I5. During the operation of pump 20, feed water is prevented from entering chamber 30 by check valve 43. Steam, however, can enter chamber 30 from boiler l0 during such period and condenses to form a strong solution of cleaning material from solid material which has been placed, in such chamber. When the pump 20 stops and the flow of feed water is interrupted, a drain 46 is opened providing a path for fluid through the tubes I5 so that steam from boiler l0 forces the solution of treating or cleaning material from chamber 39 through tubes IS, the drain being left open long enough so that live steam from boiler Ill can heat the tubes l5 to a point insuring a reaction between the cleaning material and all the scale on the inner surfaces of such tubes. Moreover, the apparatus in accordance with my invention preferably automatically closes the drain after it has remained opened a sufficient period, so that the apparatus shall not waste any cleaning compound or steam.

While I have shown the pipe 40 connected to the outlet of heater [4, I do not limit myself to such arrangement, but may connect the pipe 40 for discharging cleaning material or solution from the chamber 36 to the inlet connection I 6 of heater I4. Such alternative arrangement, although not applying the treating fiuid first to the thickest scale, ensures that some of the surfaces of the tubes 1 5 will be entirely free of scale after each operation or run of the pump and will be in such conditon at the initiation of each run. Of course, cleaning the interior tube surfaces in the round house can be practiced as at present in addition to cleaning on the road by my invention, but it is believed it will not be necessary.

While my invention is most useful as applied to locomotives I do not limit myself to such use nor to other details of the disclosure except as they are clearly expressed in the appended claims.

Further, I wish it understood that I do not limit myself to closing the drain line 46 except during the periods when pump 20 is in operation. If valve 44 is partly closed, or equivalent means used to choke the flow of steam through pipe 34 and receptacle 3!] when the pump is not running,

valve 54, whether automatic or manual, may be omitted.

What I claim is:

1. The combination with an exhaust steam feed water heater of the closed type, of a pump and connections for leading water from said pump through said heater and to a boiler, a. chamber for containing treating material, a connection from the top of said chamber to the steam space of said boiler, a connection from the bottom of said chamber to said feed water connection, a check valve between said chamber and said point of connection, an outlet from said feed water connection at a point on the opposite side of said heater from the junction point of said feed water connection and said connection from the bottomof said chamber, means for closing said outlet during the flow of feed water to the boiler but constructed to open automatically when the feed water stops, and slow acting means for closing said outlet within a predetermined time after each stoppage of the pump.

2. The combination with a locomotive of an exhaust steam feed water heater of the closed type, a pump, connectionsbetween said pump and heater and between said heater and the boiler of said locomotive whereby feed water is delivered to such boiler, a container for cleaning material, a normally open live steam line between said boiler and the upper part of said container, a conduit leading from the bottom of said container to one of said connections to the heater, a check valve in said conduit, such check valve arranged to prevent flow of water into said container during the operation of said pump, a drain pipe for said heater, and means constructed to open upon the stoppage of said pump for keeping the drain pipe closed during the operation of said pump.

3. The method of operating a closed feed water heater having a coil through which feed water flows intermittently to a boiler comprising condensing steam from said boiler in contact with a solid tannin containing brick during the periods feed water is flowing to said boiler to form a concentrated solution, forcing said solution through said coil upon cessation of fiow of feed water therethrough, and following said flow of solution through the coil by a flow of steam therethrough. 1

4. The method as set forth in claim 3 and in which the flow of steam is of limited duration.

5. In a feed water heater of the closed type having a pump and connections for forcing boiler feed water through said heater to a boiler, a drain pipe connected to said heater, and a valve in said drain pipe; means acting on said valve for keeping said drain pipe closed during operation of said pump, means acting on said valve and responsive to stoppage of said pump for automatically opening said valve shortly after stoppage of the pump, and means acting to automatically to stoppage of said pump for automatically opening said valve shortly after stoppage of the pump, and means controlled by adjustable timing means for closing the drain pipe again subsequently to said opening thereof and after a period which is relatively short compared to the average of the periods of operation of the pump.

'7. The combination with an exhaust steam feed water heater of the closed type, of a pump, connections for leading the water from said pump through said heater and into a boiler, a chamber for containing treating material, a connection from said chamber to the steam space of said boiler, a connection leading from a point near the bottom of said chamber to said feed water connection, a check valve between said chamber and said point of connection, an outlet from said feed water heater and connections at a point on the opposite side of said heater from the junction point of said feed water connections and said connection from near the bottom of said chamber, means for closing said outlet during the flow of water to the boiler but adapted to open automatically when the feed water stops flowing, and slow acting means responsive to a fluid pressure Which drops upon stoppage of said pump for closing said outlet within a predetermined time after each stoppage of the pump.

8. The combination with a locomotive of an exhaust steam feed water heater of the closed type, a pump, connections between said pump and heater and between said heater and the boiler of said locomotive whereby feed water is delivered to such boiler from said pump, a container for cleaning material, a normally open live steam line between said boiler and the said container, a connection leading from a point near the bottom of said container to one of said connections to the heater, a check valve in said last mentioned connection, such check valve arranged to prevent flow of water into said container during the operation of said pump, a drain pipe for said heater, and means responsive to the flow of water from said pump for closing said drain pipe during the operation of said pump and for opening said drain pipe during the inactivity of said p- RUDOLF M. OSTERMANN. 

